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Abstract:

The invention relates to a one-way valve (1; 1') for discharge regulation
of a tube, the one-way valve (1; 1') comprising a sealing means (9) and a
ring support (8), with the sealing means (9) being at least partially
inserted in the ring support (8), wherein the sealing means (9) comprises
a sealing element (11) and a support element (12) that has at least one
opening (10), wherein the sealing element (11) is connected to the
support element (12) by anchoring means (13) and rests on the ring
support (12) in a closed state of the one-way valve (1; 1') thereby
covering the at least one opening (10), and wherein the sealing element
(11) is of lower bending stiffness than the support element (12) and the
ring support (8). The invention furthermore relates to a tube with a tube
head (2; 2') and a container (6), wherein such a one-way valve (1; 1') is
inserted in the neck (4) of the tube head (2; 2'). Moreover the invention
relates to a method for manufacturing such a one-way valve (1; 1').

Claims:

1. A one-way valve for discharge regulation of a tube, the one-way valve
(1; 1') comprising a sealing means (9) and a ring support (8), with the
sealing means (9) being at least partially inserted in the ring support
(8), characterized in that the sealing means (9) comprises a sealing
element (11) and a support element (12) with at least one opening (10),
wherein the sealing element (11) is connected to the support element (12)
by anchoring means (13) and rests on the ring support (12) in a closed
state of the one-way valve (1; 1') thereby covering the at least one
opening (10), and wherein the sealing element (11) is of lower bending
stiffness than the support element (12) and the ring support (8).

2. The one-way valve according to claim 1, wherein the ring support (8)
and the support element (12) are integrally formed, in particular
integrally moulded.

3. The one-way valve according to claim 1 or 2, wherein the sealing
element (11) consists of a soft component and the support element (12)
and the ring support (8) consist of a hard component.

4. The one-way valve according to one of the preceding claims, wherein
the sealing element (11) of the sealing means (9) is discoidal or has a
discoidal part that rests on the ring support (8) in the closed state of
the one-way valve (1; 1').

5. The one-way valve according to one of the preceding claims, wherein
the ring support (8) is provided with positioning means (22) on its outer
surface.

6. The one-way valve according to one of the preceding claims, wherein as
anchoring means (13) the sealing means (11) comprises an anchor (14) and
the support element (12) comprises a recess (16) for receiving the anchor
(14) or part of the anchor (14).

7. A tube with a tube head (2; 2') and a container (6), wherein the tube
head (2; 2') comprises a port (20), a hollow neck (4) and a shoulder (5),
with the port (20) being connected to the neck (4) and the neck (4) being
connected to the container (6) via the shoulder (5), characterized by a
one-way valve (1; 1') according to one of the preceding claims, the
one-way valve (1; 1') being inserted in the neck (4) with the ring
support (8) of the one-way valve (1; 1') being sealingly fixed to the
neck (4), wherein the sealing element (11) and the ring support (8) of
the one-way valve (1; 1') are designed such that the sealing element (11)
rests on the ring support (8) when the tube is not compressed and that
the sealing element (11) is lifted off the ring support (8) and at least
partly off the support element (12) when the tube is compressed thereby
enabling the one-way valve (1; 1') to be in an open state.

8. The tube according to claim 7, wherein the port (20) has a smaller
inner diameter than the bore of the neck (4) and wherein the ring support
(8) of the one-way valve (1, 1') is fixed to the neck (4) such that a
head space (18) is provided between the sealing element (11) of the
sealing means (9) of the one-way valve (1, 1') and the port (20).

9. The tube according to claim 7 or 8, wherein the ring support (8) is
fixed to the neck (4) such that the sealing element (11) is bent so far
into the head space (18) that it closes the entrance to the port (20)
when the tube is compressed and the internal pressure (p) of the tube
exceeds a certain limit.

10. The tube according to one of the claims 7 to 9, wherein the ring
support (8) of the one-way valve (1; 1') is fixed to the neck (4) by
force fitting.

11. A method for manufacturing a one-way valve (1; 1') according to one
of the claims 1 to 6, characterized by the following steps: forming the
ring support (8) and the support element (12) through injection moulding
of a hard component, in particular as one piece, cooling of the formed
ring support (8) and the formed support element (12), and forming the
sealing element (11) through injection moulding of a soft component on
the ring support (8) and the support element (12).

12. The method of claim 11, wherein for cooling of the formed ring
support (8) and of the formed support element (12) the temperature
decreases from about 100 to about 50 degrees Celsius.

Description:

TECHNICAL FIELD

[0001] The invention relates to a one-way valve for discharge regulation
in tubes, a tube with such a one-way valve and a method for manufacturing
such a one-way valve according to the preambles of the independent
claims.

BACKGROUND

[0002] After dispensing of some of their contents plastic tubes usually
tend to suck in ambient air due to recovery of the tube container which
causes a negative pressure inside the tube. The ambient air can react
with the contents of the tube container, in particular if the contents
are oxygen-sensitive. The fill level of the tube can typically not be
inspected visually, as the tube container retakes its original shape due
to the sucked in ambient air.

[0003] Furthermore, dispensing very liquid contents as drops from known
tubes is often not possible as the potentially high internal pressure can
lead to the drops being dispensed too fast or in form of a jet.

[0004] Japanese patent application JP 2004-034996 A discloses a tube with
a tube container, a tubular mouth and a cap member. When the cap member
is mounted on the tubular mouth such that an internal space of the
tubular mouth is hermetically sealed, a vent passage is formed inside the
cap member and around the outer periphery of the tubular mouth,
respectively. When the cap member is removed, the internal space of the
tubular mouth can communicate with the ambient air via the vent passage
such that the contents of the tube container are not accidentally sucked
out due to negative pressure.

[0005] From the German patent application DE 102 13 124 A1 there is known
a valve for automatically closing a tube. The valve has radial slots on
the inside and on the outside at a lower level. Radially outwardly
projecting stars are formed at an upper level of the valve. For mounting
in a tube mouth the valve is turned inside out. The radial slots then
serve as anchoring means for fastening the valve at the lower end of the
tube mouth. The stars are now inwardly projecting and form a sealing
rosette-shaped valve. For fixating the rosette-shaped valve a clamping
collar is employed.

[0006] Patent document U.S. Pat. No. 7,222,751 B2 relates to collapsible
tubes for storing and distributing liquid to pasty products keeping them
protected from ambient air. A tube head is disclosed that is fitted with
a non-return valve to prevent pollution from ambient air due to
relaxation of the pressure on the skirt. The valve is inserted in the
neck of the tube head. The valve comprises a sealing means that is in
contact with a ring support having an opening. The sealing means is
connected to an elastically deformable support element. The sealing means
closes the opening when the tube is not compressed. When pressure is
applied to the skirt of the tube, the product applies pressure on the
sealing means and the sealing means is lifted. When the pressure is
removed, the elastic return of the skirt causes a negative pressure that
pushes the sealing means into contact with the ring support thereby
closing the opening.

[0007] Known valves by which the entrance of ambient air into the tube
container can be prevented after contents have been dispensed usually
require a lot of space inside the tube neck. The known valves often
consist of two parts and their sealing area is not adjustable so that the
known valves often suffer from insufficient sealing properties. The known
valves usually have to be mounted separately which leads to additional
and often high costs.

DISCLOSURE OF THE INVENTION

[0008] It is an object of the invention to provide a one-way valve that
requires little available space and that can be easily mounted. It is a
further object of the invention to provide a tube with such a one-way
valve and a method for manufacturing such a one-way valve.

[0009] In order to implement these and still further objects of the
invention, which will become more readily apparent as the description
proceeds, a one-way valve for discharge regulation of a tube is provided.
The one-way valve comprises a sealing means and a ring support. The
sealing means is at least partially inserted in the ring support. The
sealing means comprises a sealing element and a support element wherein
the sealing element is connected with the support element by anchoring
means. The support element has at least one opening. The support element
and the ring support are connected to each other and are preferably
formed in one piece, i.e. formed integrally, most preferably molded
integrally. The anchoring means can be formed by the sealing element
and/or the support element. The sealing element is of lower bending
stiffness than the support element and the ring support. In particular,
the sealing element consists of a soft component and the support element
and the ring support consist of a hard component.

[0010] The soft component is preferably given by a thermoplastic elastomer
(TPE), in particular by a thermoplastic elastomer with a Shore hardness
of about 40 Shore A. Preferentially a thermoplastic elastomer based on a
styrene-ethylene-butylene-styrene (SEBS) block copolymer is used as soft
component. The hard component is preferably given by a thermoplastic
polymer, in particular by a polypropylene (PP) with preferentially a
Shore hardness of about 70 Shore D. Preferably a polypropylene copolymer
is used as hard component.

[0011] The sealing element rests on the ring support in a closed state of
the one-way valve, thereby closing the at least one opening of the
support element. In an open state of the one-way valve the sealing
element is lifted off the ring support and at least partly off the
support element, thereby uncovering the at least one opening. The sealing
element is preferably shaped like a disc or has at least a disc-shaped
part. The ring support and the support element form the body or casing of
the one-way valve with the sealing element functioning as membrane.

[0012] Furthermore, a tube with a tube head and a container is provided.
The tube head comprises a port, a hollow neck and a shoulder, wherein the
port is connected with the shoulder via the neck and the shoulder is
connected to the container. The tube comprises a one-way valve according
to the invention that is inserted in the neck of the tube head. The ring
support of the one-way valve is sealingly fixed to the neck. The outer
surface of the ring support is thereby attached in such a manner to the
inner surface of the neck that contents can not pass between them. In
particular, the ring support is fixed to the neck by force fitting (also
referred to as press fit or interference fit). The sealing element and
the ring support of the one-way valve are designed such that the sealing
element rests on the ring support when the tube is not compressed and
that the sealing element is lifted off the ring support and at least
partly off the support element when the tube is compressed thereby
changing the state of the one-way valve to an open state, uncovering the
at least one opening of the support element. That is, the bending
stiffness of the sealing element and the bending stiffness of the ring
support and the support element are thus that the bending stiffness of
the sealing element is sufficiently low in comparison to the bending
stiffness of the ring support and of the support element so that the
sealing element is lifted off the ring support and at least partly of the
support element when the tube is compressed.

[0013] Furthermore, a method for manufacturing a one-way valve according
to the invention is provided. The one-way valve is manufactured by
two-component injection moulding with the two components being a hard
component for forming the ring support and the support element of the
one-way valve and a soft component for forming the sealing element of the
one-way valve, wherein the ring support and the support element are
preferentially integrally formed. The hard component and the soft
component are as defined above. In a first step the ring support and the
support element are formed through injection moulding of the hard
component. Thereafter, the ring support and the support element, which
preferable form one piece, are turned around/upside down in the mould.
Then the sealing element is formed on the hard component, i.e. on the
ring support and on the support element, through injection moulding of
the soft component. Between injection moulding of the hard component and
injection moulding of the soft component sufficient cooling of the hard
component, i.e. the ring support and the support element, is required and
provided to ensure that there is no inseparable, thermal connection
formed between the soft component and the hard component. For the hard
component being polypropylene the mould release temperature is about 100
degrees Celsius, with an end temperature of about 50 degrees Celsius
being preferably reached when the soft component is injection moulded.

[0014] As the one-way valve is entirely formed through injection moulding
there are advantageously no mounting steps involved in its fabrication.
For providing a tube head of a tube with a one-way valve according to the
invention, the one-way valve is pressed into the neck of the tube head in
the direction towards the port and assembled to the neck by force fitting
such that the ring support is fitted to the inner surface of the neck.
The one-way valve is held in the tube head by its ring support, which is
radially arranged in the neck, and sealed towards the neck of the tube
head. As the design of the one-way valve is rather compact, it requires
little installation space leaving more space for e.g. the contents of the
tube and it can be easily attached inside a tube head.

[0015] Once compression of the tube has ceased and the internal pressure
in the tube container decreases, flow of ambient air into the container
is advantageously prevented as the sealing element of the one-way valve
again comes to rest on the ring support, thereby closing the at least one
opening of the support member so that ambient air can not enter the
container. Similarly, contents that have entered the port and/or a
cannula during compression and that have hence already been in contact
with ambient air are prevented from entering the container by the sealing
element resting on the ring support.

[0016] Preventing ambient air and with ambient air contaminated contents,
respectively, from being sucked into the tube container is especially
important if the contents are likely to react with oxygen, i.e. are
oxygen-sensitive. Furthermore, by preventing ambient air from being
sucked into the container, the tube container is kept from taking its
uncompressed shape thus making the fill level of the tube visible.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Further advantageous features and applications of the invention can
be found in the depending claims as well as in the following description
of the drawings illustrating the invention. In the drawings like
reference signs designate the same or similar parts throughout the
several figures of which:

[0018] FIG. 1 depicts a sectional view of a tube head with a first
embodiment of a one-way valve of the invention (FIG. 1a)), a sectional
view of the first embodiment of a one-way valve of the invention (FIG.
1b)), and an enlarged detail of the sectional view of the tube head shown
in FIG. 1a) (FIG. 1c)),

[0019] FIG. 2 depicts a further sectional view of the first embodiment of
a one-way valve of the invention shown in FIG. 1b),

[0020] FIG. 3 depicts a sectional view of a second embodiment of a one-way
valve of the invention, the sectional view running through the openings
of the ring support along a plane that lies parallel and spaced apart
from a plane in which the longitudinal axis of the one-way valve lies,

[0021]FIG. 4 depicts a sectional view of the second embodiment of a
one-way valve of the invention, the sectional view running along a plane
in which the longitudinal axis of the one-way valve lies and that lies
parallel and spaced apart from the plane of the sectional view in FIG. 3,

[0022] FIG. 5 depicts a plan view from below of the second embodiment of a
one-way valve of the invention without sealing element,

[0023] FIG. 6 depicts a perspective view of the second embodiment of a
one-way valve of the invention without sealing element,

[0024] FIG. 7 depicts a sectional view of a tube head with the first
embodiment of a one-way valve of the invention in open or opening state,
respectively,

[0025] FIG. 8 depicts a sectional view of a tube head with the first
embodiment of a one-way valve of the invention in closed state,

[0026] FIG. 9 depicts a sectional view of a further embodiment of a tube
head with the second embodiment of a one-way valve of the invention in
closed state, and

[0027] FIG. 10 depicts a sectional view of a tube head with the first
embodiment of the one-way valve of the invention moving towards an open
state in which it closes the entrance to the port.

[0028] The dimensions in the Figures are given by way of example and
without any limitation.

Mode(s) for Carrying out the Invention

[0029] FIGS. 1 and 2 show a first embodiment 1 of a one-way valve
according to the invention (FIGS. 1b) and 2) and a tube head 2 of a tube
according to the invention (FIG. 1a)) into which the one-way valve 1 has
been inserted. The tube head 2 comprises a port 20 that--in this
particular embodiment of the tube head 2--extends into a cannula 3, a
neck 4 and a shoulder 5, that is connected to the port 20 and hence the
cannula 3 via the neck 4. The shoulder 5 connects to the container 6 of
the tube of the invention. Of course, a tube head 2 without a cannula 3
can be provided. For insertion, the one-way valve 1 is moved into the
tube head 2 in the direction indicated by the arrow 7, i.e. towards the
port 20, and pressed into the neck 4 thereby forming a press fit with the
neck 4. The neck 4 comprises a thread on its outside so that a cap can be
screwed onto the tube head 2.

[0030] The one-way valve 1 comprises a ring support 8 and a sealing means
9 that is inserted in the ring support 8. The sealing means 9 comprises a
sealing element 11 and a support element 12 to which the sealing element
11 is connected by anchoring means 13. The support element 12 has
openings 10 and is connected with the ring support 8 (confer FIGS. 4 to
6). The anchoring means 13 are preferably formed by the sealing element
11 and the support element 12, in particular by the sealing element 11
having an anchor 14 with a preferentially radially extending disc 15 and
by the support element 12 having a preferentially annular recess 16 in
which the disc 15 is held such that the sealing element 11 can not be
entirely lifted off the support element 12 in the direction towards the
port 3 (see FIG. 2). The sealing element 11 is only anchored in the
support element 12. There is no thermal connection between the sealing
element 11 and the support element 12 and between the sealing element 11
and the ring support 8, respectively, so that the sealing element 11 can
be lifted off the ring support 8 and the support element 12 to the extent
to which it is not held by the anchoring means 13 on the support element
12. The sealing element 11 has preferably the shape of a disc extending
in radial direction.

[0031] The sealing element 11 and the support element 12 with the openings
10 are preferably formed as described below for a second embodiment 1' of
a one-way valve according to the invention.

[0032] The bending stiffness of the sealing element 11 is lower than the
bending stiffness of the ring support 8 and of the support element 12. To
achieve this, the sealing element 11 preferably consists of a soft
component whereas the support element 12 and the ring support 8 consist
of a hard component, with the soft component and the hard component not
being thermally connected. For the definition of the soft component and
the hard component it is referred to the introductory part of the
description.

[0033] FIGS. 3 to 6 show a second embodiment 1' of a one-way valve of the
invention. For ease of presentation the sealing element 11 is not shown
in FIGS. 5 and 6. The support element 12 has exemplarily four openings 10
arranged coaxially around the longitudinal axis of the one-way valve 1'
through which contents can pass from a tube container 6 to a port 20 of a
tube head. There can be more or less than four openings 10 provided in
the support means 12. In a closed state of the one-way valve 1' the
openings 10 are covered by the sealing element 11. Reference sign 23 in
FIGS. 5 and 6 designates where the anchor 14 is located in support
element 12. The sealing element 11 and the support element 12 of the
first embodiment 1 of a one-way valve of the invention shown in FIGS. 1
and 2 may be formed as shown in FIGS. 3 to 6.

[0034] The ring support 8 of the second embodiment 1' of the one-way valve
of the invention depicted in FIGS. 3 to 6 and also 9 is provided with
positioning means 22 on its outer surface for more accurate positioning
of the one-way valve 1' on the inside of a neck 4 of a tube head. The
positioning means 22 are preferably formed as outwardly projecting
shoulder on the outer surface of the ring support 8.

[0035] When connecting the one-way valve 1, 1' with the neck 4 of the tube
head 2 through press fitting, the radially arranged ring support 8 is
sealingly connected to the inner surface of the neck 4 such that the
one-way valve 1, 1' is held by the ring support 8 within the tube head 2
and sealed towards the inner surface of the neck 4. FIG 1c) shows the
sealing connection of the outer surface of the ring support 8 with the
inner surface of the neck 4 in detail. The same applies to the second
embodiment 2' of the tube head shown in FIG. 9 and described below.

[0036] The port 20 has in particular a smaller inner diameter than the
bore of the neck 4. If the port 20 extends into a cannula with a bore 17,
then the diameter of the bore 17 of the cannula 3 is in particular
smaller than the bore of the neck 4. A head space 18 is provided between
the one-way valve 1, 1' and the port 20 and the cannula 3, respectively,
in that the ring support 8 of the one-way valve 1, 1' is fixed to the
neck spaced apart (in the longitudinal direction) from the port 20 (and
the cannula 3 and its bore 17, respectively, if provided). The head space
18 is located between the sealing element 11 and the port 20 and the
distal end of the cannula 3, respectively. The distal end of the cannula
3 is that end of the cannula 3 that is further away from the outlet 19 of
the cannula 3 and located closer to neck 4. That is, the one-way valve 1,
1' is only pressed so far into the neck 4 of the tube head 2, 2' that the
head space 18 is formed (see FIG. 9 for the second embodiment 2' of a
tube head). The head space 18 provides space for the sealing element 11
when it is lifted off the ring support 8 upon compression of the tube.

[0037] FIG. 7 shows the tube head 2 shown in FIG. 1a) with the tube and
its container 6, respectively, being compressed to dispense contents
through the port 20 and further through the bore 17 of the optional
cannula 3. Being of lower stiffness than the ring support 8 and the
support element 12 and preferably of a soft component, the sealing
element 11 is lifted off the ring support 8 and partly off the support
element 12 due to the inner pressure in the tube container 6 and uncovers
thereby the openings 10 in the support element 12. The contents of the
container 6 can now pass through the openings 10 of the support element
12 and further through the port 20, flow towards the outlet 19 of the
cannula 3 and be dispensed. The black arrows in FIG. 7 indicate the
direction of flow of the contents.

[0038] When the pressure onto the tube is taken back, the inner pressure
in the container 6 collapses and the sealing element 11 falls back onto
the ring support 8 and blocks the return flow of the contents through the
openings 10 into the container 6 in addition to preventing that ambient
air is sucked into the container 6. This is depicted in FIG. 8 where the
arrows depict the direction of the return flow of the contents and the
direction of flow of the ambient air. The tube head 2 shown in FIGS. 1a),
7 and 8 can of course also be provided with the second embodiment 1' of a
one-way valve according to the invention shown in FIGS. 3 to 6.

[0039] FIG. 9 shows a second embodiment 2' of a tube head of a tube
according to the invention, wherein the cannula 3 is dispensed with, i.e.
the contents of the tube container 6 is directly dispensed from the port
20. The tube head 2' is provided with the second embodiment 1' of the
one-way valve of the invention as depicted in FIGS. 3 to 6. The inner
surface of the neck 4 is provided with a counterpart 24 to the
positioning means 22 on the outer surface of the ring support 8 of the
one-way valve 1'. With the positioning means 22 given by an outwardly
projecting shoulder, its counterpart 24 on the inner surface of the neck
4 is preferably formed as inwardly projecting shoulder 24. The outwardly
projecting shoulder 22 of the ring support 8 abuts against the inwardly
projecting shoulder 24 when the one-way valve 1' is pressed into the neck
4, thereby facilitating positioning of the one-way valve 1' inside the
neck 4 and forming of the head space 18, as the distance from the
inwardly projecting shoulder 24 of the neck 4 to the port 20 in
longitudinal direction in relation to the distance between the outwardly
projecting shoulder 22 of the ring support 8 to the upper side of the
sealing element 11 in longitudinal direction defines the height of the
head space 18. Of course, the second embodiment 2' of the tube head can
also be provided with the first embodiment 1 of the one-way valve
according to the invention as depicted in FIGS. 1, 2, 7, 8 and 10.

[0040] The dispensed amount of fluid, in particular the dropping rate,
i.e. the amount of drops dispensed during a certain time interval, is
automatically adjusted in that the sealing element 11 of the one-way
valve 1, while being lifted off the ring support 8 and partly off the
support element 12 during application of the pressure `p` to the
container 6, moves sufficiently far into the head space 18 that the
passage `a` between the tube head 2, in particular its top wall 21, and
the sealing element 11 is reduced/narrowed so that less contents can pass
through the port 20 and the bore 17 of the optionally provided cannula 3.
The larger the pressure `p` is, the narrower the passage `a` becomes.
This is especially important for contents of low viscosity. The sealing
element 11 has in particular the form of a disc that is bent towards the
top wall 21 upon pressure application with its rim portion being lifted
off the ring support 8 and partly off the support element 12. This is
shown in FIG. 10 in detail with the arrows indicating the direction of
the pressure `p` and the direction of contents flow. If the internal
pressure `p` in the tube container 6 exceeds a certain limit, then the
sealing element 11 is moved or bent, respectively, so far into the head
space 18 that it abuts against the top wall 21 and thereby closes the
entrance to the port 20 and, hence, to the bore 17 in the cannula 3 (if
provided), thereby preventing that contents enters the port 20 and is
dispensed. The top wall 21 represents the transition between from the
neck 4 to the port 20. For the sealing element 11 being disc-shaped, its
annular rim touches the inner surface of the top wall 21 if the pressure
limit is exceeded, thereby preventing contents from entering the port 20
and the bore 17, the latter if a cannula 3 is provided. Thus regulation
of the dispensed amount of contents can advantageously be achieved. In
FIG. 10 the first embodiment 1 of a one-way valve according to the
invention is depicted. Alternatively, the second embodiment 1' depicted
in FIGS. 3 to 6 and 9 could have been used and shown.

[0041] It is to be understood that while certain embodiments of the
present invention have been illustrated and described herein, it is not
to be limited to the specific embodiments described and shown.